We are studying steroid metabolism in C. elegans and are asking how steroids regulate gonadal development, function and aging. Our approach is to establish the pathway of wild-type metabolism and then subsequently analyze mutants altered in gonadal development and function and correlate these defects with their aberrations in steroid metabolism. By using mutants we may be able to dissect specific actions of steroids into their regulation of gonadal development and to see how their steroid metabolism is altered as their gonads age. By understanding how steroids regulate normal gonadal function and by knowing these steroid levels are altered in the aging gonad, we may be able to understand how gonadal aging is regulated.